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1.
Toxins (Basel) ; 15(6)2023 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-37368679

RESUMEN

Phα1ß (PnTx3-6) is a neurotoxin from the spider Phoneutria nigriventer venom, originally identified as an antagonist of two ion channels involved in nociception: N-type voltage-gated calcium channel (CaV2.2) and TRPA1. In animal models, Phα1ß administration reduces both acute and chronic pain. Here, we report the efficient bacterial expression system for the recombinant production of Phα1ß and its 15N-labeled analogue. Spatial structure and dynamics of Phα1ß were determined via NMR spectroscopy. The N-terminal domain (Ala1-Ala40) contains the inhibitor cystine knot (ICK or knottin) motif, which is common to spider neurotoxins. The C-terminal α-helix (Asn41-Cys52) stapled to ICK by two disulfides exhibits the µs-ms time-scale fluctuations. The Phα1ß structure with the disulfide bond patterns Cys1-5, Cys2-7, Cys3-12, Cys4-10, Cys6-11, Cys8-9 is the first spider knottin with six disulfide bridges in one ICK domain, and is a good reference to other toxins from the ctenitoxin family. Phα1ß has a large hydrophobic region on its surface and demonstrates a moderate affinity for partially anionic lipid vesicles at low salt conditions. Surprisingly, 10 µM Phα1ß significantly increases the amplitude of diclofenac-evoked currents and does not affect the allyl isothiocyanate (AITC)-evoked currents through the rat TRPA1 channel expressed in Xenopus oocytes. Targeting several unrelated ion channels, membrane binding, and the modulation of TRPA1 channel activity allow for considering Phα1ß as a gating modifier toxin, probably interacting with S1-S4 gating domains from a membrane-bound state.


Asunto(s)
Miniproteínas Nodales de Cistina , Venenos de Araña , Arañas , Toxinas Biológicas , Ratas , Animales , Canal Catiónico TRPA1/genética , Arañas/química , Neurotoxinas , Espectroscopía de Resonancia Magnética , Disulfuros , Venenos de Araña/farmacología , Venenos de Araña/química
2.
Curr Protein Pept Sci ; 24(5): 365-379, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37018532

RESUMEN

Ion channels play critical roles in generating and propagating action potentials and in neurotransmitter release at a subset of excitatory and inhibitory synapses. Dysfunction of these channels has been linked to various health conditions, such as neurodegenerative diseases and chronic pain. Neurodegeneration is one of the underlying causes of a range of neurological pathologies, such as Alzheimer's disease (AD), Parkinson's disease (PD), cerebral ischemia, brain injury, and retinal ischemia. Pain is a symptom that can serve as an index of the severity and activity of a disease condition, a prognostic indicator, and a criterion of treatment efficacy. Neurological disorders and pain are conditions that undeniably impact a patient's survival, health, and quality of life, with possible financial consequences. Venoms are the best-known natural source of ion channel modulators. Venom peptides are increasingly recognized as potential therapeutic tools due to their high selectivity and potency gained through millions of years of evolutionary selection pressure. Spiders have been evolving complex and diverse repertoires of peptides in their venoms with vast pharmacological activities for more than 300 million years. These include peptides that potently and selectively modulate a range of targets, such as enzymes, receptors, and ion channels. Thus, components of spider venoms hold considerable capacity as drug candidates for alleviating or reducing neurodegeneration and pain. This review aims to summarize what is known about spider toxins acting upon ion channels, providing neuroprotective and analgesic effects.


Asunto(s)
Analgesia , Venenos de Araña , Arañas , Animales , Venenos de Araña/farmacología , Neuroprotección , Calidad de Vida , Canales Iónicos , Péptidos/farmacología , Péptidos/uso terapéutico , Dolor/tratamiento farmacológico
3.
Cells ; 12(7)2023 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-37048096

RESUMEN

Dendritic cells (DCs) vaccine is a potential tool for oncoimmunotherapy. However, it is known that this therapeutic strategy has failed in solid tumors, making the development of immunoadjuvants highly relevant. Recently, we demonstrated that Phoneutria nigriventer spider venom (PnV) components are cytotoxic to glioblastoma (GB) and activate macrophages for an antitumor profile. However, the effects of these molecules on the adaptive immune response have not yet been evaluated. This work aimed to test PnV and its purified fractions in DCs in vitro. For this purpose, bone marrow precursors were collected from male C57BL6 mice, differentiated into DCs and treated with venom or PnV-isolated fractions (F1-molecules < 3 kDa, F2-3 to 10 kDa and F3->10 kDa), with or without costimulation with human GB lysate. The results showed that mainly F1 was able to activate DCs, increasing the activation-dependent surface marker (CD86) and cytokine release (IL-1ß, TNF-α), in addition to inducing a typical morphology of mature DCs. From the F1 purification, a molecule named LW9 was the most effective, and mass spectrometry showed it to be a peptide. The present findings suggest that this molecule could be an immunoadjuvant with possible application in DC vaccines for the treatment of GB.


Asunto(s)
Glioblastoma , Venenos de Araña , Ratones , Masculino , Humanos , Animales , Glioblastoma/terapia , Venenos de Araña/farmacología , Ratones Endogámicos C57BL , Diferenciación Celular , Células Dendríticas
4.
Sci Rep ; 13(1): 2389, 2023 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-36765114

RESUMEN

Spiders are important predators of insects and their venoms play an essential role in prey capture. Spider venoms have several potential applications as pharmaceutical compounds and insecticides. However, transcriptomic and proteomic analyses of the digestive system (DS) of spiders show that DS is also a rich source of new peptidase inhibitor molecules. Biochemical, transcriptomic and proteomic data of crude DS extracts show the presence of molecules with peptidase inhibitor potential in the spider Nephilingis cruentata. Therefore, the aims of this work were to isolate and characterize molecules with trypsin inhibitory activity. The DS of fasting adult females was homogenized under acidic conditions and subjected to heat treatment. After that, samples were submitted to ion exchange batch and high-performance reverse-phase chromatography. The fractions with trypsin inhibitory activity were confirmed by mass spectrometry, identifying six molecules with inhibitory potential. The inhibitor NcTI (Nephilingis cruentata trypsin inhibitor) was kinetically characterized, showing a KD value of 30.25 nM ± 8.13. Analysis of the tertiary structure by molecular modeling using Alpha-Fold2 indicates that the inhibitor NcTI structurally belongs to the MIT1-like atracotoxin family. This is the first time that a serine peptidase inhibitory function is attributed to this structural family and the inhibitor reactive site residue is identified. Sequence analysis indicates that these molecules may be present in the DS of other spiders and could be associated to the inactivation of prey trypsin (serine peptidase) ingested by the spiders.


Asunto(s)
Venenos de Araña , Arañas , Femenino , Animales , Inhibidores de Tripsina/farmacología , Tripsina , Proteómica , Venenos de Araña/farmacología , Venenos de Araña/química , Sistema Digestivo , Serina
5.
Mol Neurobiol ; 59(7): 4436-4452, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35570263

RESUMEN

CTK 01512-2 toxin is a recombinant peptide of the Phα1ß version derived from the venom of the Phoneutria nigriventer spider. It acts as an N-type voltage-gated calcium channel (VGCC) blocker and shows a prolonged effect on preventing and reducing nociception. Herein, CTK 01512-2 was tested on two models of persistent pain, the chronic post-ischemia pain (CPIP) and the paclitaxel-induced peripheral neuropathy, to evaluate its systemic, intrathecal, and intracerebroventricular effects on mechanical hypersensitivity and thermal allodynia. Glial cell viability was also investigated using the MTT test. The results showed that CTK 01512-2 intrathecal and systemic treatments reduced the mechanical hypersensitivity induced by CPIP, mainly between 1-4 h after its administration. Additionally, intrathecal treatment reduced the CPIP-induced thermal allodynia. In its turn, the intracerebroventricular treatment showed mechanical antihyperalgesic and thermal antiallodynic effects in the paclitaxel-induced peripheral neuropathy. These data reinforce the therapeutic potential of CTK 01512-2 to treat persistent pain conditions and offer a perspective to use the systemic route. Moreover, CTK 01512-2 increased the glial cell viability in the MTT reduction assay, and it may indicate a new approach to managing chronic pain. The results found in this study help to pave new perspectives of pain relief treatments to patients affected by chronic pain.


Asunto(s)
Dolor Crónico , Venenos de Araña , omega-Conotoxinas , Animales , Bloqueadores de los Canales de Calcio/farmacología , Dolor Crónico/tratamiento farmacológico , Modelos Animales de Enfermedad , Humanos , Hiperalgesia/tratamiento farmacológico , Paclitaxel/farmacología , Paclitaxel/uso terapéutico , Venenos de Araña/farmacología , Venenos de Araña/uso terapéutico , omega-Conotoxinas/farmacología , omega-Conotoxinas/uso terapéutico
6.
Peptides ; 146: 170648, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34537257

RESUMEN

Peptides are molecules that have emerged as crucial candidates for the development of anticancer drugs. Spider venoms are a rich source of peptides (venom peptides - VPs) with biological effects. VPs have been tested as adjuvants in the activation of cells of the immune system with the aim of improving immunotherapies for the treatment of neoplasms. In the present study, the effects of SNX-482, a peptide from the African tarantula Hysterocrates gigas, on macrophages were described. The results showed that the peptide activated M0-macrophages, increasing costimulatory molecules (CD40, CD68, CD80, CD83, CD86) involved in antigen presentation, and also augmenting the checkpoint molecules PD-L1, CTLA-4 and FAS-L; these effects were not concentration-dependent. SNX-482 also increased the release of IL-23 and upregulated the expression of ccr4, ifn-g, gzmb and pdcd1, genes important for the anticancer response. The pretreatment of macrophages with the peptide did not interfere in the modulation of T cells, and macrophages previously polarized to M1 and M2 profile did not respond to SNX-482. These findings represent the expansion of knowledge about the use of VPs in drug discovery, pointing to a potential new candidate for anticancer immunotherapy. Considering that most immunotherapies target the adaptive system, the modulation of macrophages (an innate immune cell) by SNX-482 is especially relevant.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Activación de Macrófagos/efectos de los fármacos , Venenos de Araña/química , Arañas/química , Animales , Antígenos CD/inmunología , Línea Celular Tumoral , Polaridad Celular , Citocinas/metabolismo , Ensayo de Inmunoadsorción Enzimática , Expresión Génica , Activación de Macrófagos/inmunología , Ratones , Neoplasias/genética , Neoplasias/inmunología , Venenos de Araña/farmacología
7.
Brain Res ; 1764: 147438, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-33753067

RESUMEN

Central sensitization (CS) is characteristic of difficult to treat painful conditions, such as fibromyalgia and neuropathies and have sexual dimorphism involved. The calcium influx in nociceptive neurons is a key trigger for CS and the role of Cav2.1 and Cav2.2 voltage gated calcium channels (VGCC) in this role were evidenced with the use of ω-agatoxin IVA and ω-agatoxin MVIIA blockers, respectively. However, the participation of the α1 subunit of the voltage-gated channel Cav2.3, which conducts R-type currents, in CS is unknown. Furthermore, the role of sexual differences in painful conditions is still poorly understood. Thus, we investigated the role of Cav2.3 in capsaicin-induced secondary hyperalgesia in mice, which serve as a CS model predictive of the efficacy of novel analgesic drugs. Capsaicin injection in C57BL/6 mice caused secondary hyperalgesia from one to five hours after injection, and the effects were similar in male and female mice. In female but not male mice, intrathecal treatment with the Cav2.3 inhibitor SNX-482 partially and briefly reversed secondary hyperalgesia at a dose (300 pmol/site) that did not cause adverse effects. Moreover, Cav2.3 expression in the dorsal root ganglia (DRG) and spinal cord was reduced by intrathecal treatment with an antisense oligonucleotide (ASO) targeting Cav2.3 in female and male mice. However, ASO treatment was able to provide a robust and durable prevention of secondary hyperalgesia caused by capsaicin in female mice, but not in male mice. Thus, our results demonstrate that Cav2.3 inhibition, especially in female mice, has a relevant impact on a model of CS. Our results provide a proof of concept for Cav2.3 as a molecular target. In addition, the result associated to the role of differences in painful conditions linked to sex opens a range of possibilities to be explored and needs more attention. Thus, the relevance of testing Cav2.3 inhibition or knockdown in clinically relevant pain models is needed.


Asunto(s)
Canales de Calcio Tipo R/genética , Proteínas de Transporte de Catión/genética , Sensibilización del Sistema Nervioso Central/genética , Hiperalgesia/genética , Animales , Bloqueadores de los Canales de Calcio/farmacología , Canales de Calcio Tipo R/efectos de los fármacos , Capsaicina , Proteínas de Transporte de Catión/efectos de los fármacos , Sensibilización del Sistema Nervioso Central/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Femenino , Ganglios Espinales/metabolismo , Técnicas de Silenciamiento del Gen , Hiperalgesia/inducido químicamente , Hiperalgesia/tratamiento farmacológico , Masculino , Ratones , Ratones Endogámicos C57BL , Oligonucleótidos Antisentido/farmacología , Caracteres Sexuales , Venenos de Araña/farmacología , Médula Espinal/metabolismo
8.
J Biochem ; 170(1): 51-68, 2021 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-33599263

RESUMEN

Immunomodulation has been considered an important approach in the treatment of malignant tumours. However, the modulation of innate immune cells remains an underexplored tool. Studies from our group demonstrated that the Phoneutria nigriventer spider venom (PnV) administration increased the infiltration of macrophage in glioblastoma, in addition to decreasing the tumour size in a preclinical model. The hypothesis that PnV would be modulating the innate immune system led us to the main objective of the present study: to elucidate the effects of PnV and its purified fractions on cultured macrophages. Results showed that PnV and the three fractions activated macrophages differentiated from bone marrow precursors. Further purification generated 23 subfractions named low weight (LW-1 to LW-12) and high weight (HW-1 to HW-11). LW-9 presented the best immunomodulatory effect. Treated cells were more phagocytic, migrated more, showed an activated morphological profile and induced an increased cytotoxic effect of macrophages on tumour cells. However, while M1-controls (LPS) increased IL-10, TNF-alpha and IL-6 release, PnV, fractions and subfractions did not alter any cytokine, with the exception of LW-9 that stimulated IL-10 production. These findings suggest that molecules present in LW-9 have the potential to be used as immunoadjuvants in the treatment of cancer.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Glioblastoma/terapia , Inmunoterapia , Macrófagos/efectos de los fármacos , Venenos de Araña/farmacología , Animales , Células Cultivadas , Glioblastoma/metabolismo , Glioblastoma/patología , Humanos , Ratones
9.
Eur J Pharmacol ; 891: 173672, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33190801

RESUMEN

Agents that modulate the activity of high-voltage gated calcium channels (HVCCs) exhibit experimentally and clinically significant effect by relieving visceral pain. Among these agents, the toxins Phα1ß and ω-conotoxin MVIIA effectively reduce chronic pain in rodent models. The molecular mechanisms underlying the chronic pain associated with acute pancreatitis (AP) are poorly understood. Hypercalcemia is a risk factor; the role of cytosolic calcium is considered to be a modulator of pancreatitis. Blockade of Ca2+ signals may be useful as a prophylactic treatment of pancreatitis. We explored the pathophysiological roles of three peptide toxins: Phα1ß and its recombinant form CTK 01512-2-blockers of TRPA1 receptor and HVCCs and ω-conotoxin MVIIA, a specific blocker of N-type calcium channels in cerulein-induced AP. Cerulein injection elicits AP in rats, evidenced by an increase in hyperalgesic pain, inflammatory infiltration, amylase and lipase secretion, and reactive oxygen species, TNF-α, and p65 NF-κB levels. These effects of cerulein-induced AP were abolished by Phα1ß and its recombinant form CTK 01512-2, whereas ω-conotoxin MVIIA had no effect on the induced increase in pancreatic enzyme secretion. Our results demonstrate that Phα1ß and CTK 01512-2 toxins-antagonists of HVCCs and TRPA1 receptor presented an effective response profile, in the control of nociception and inflammatory process in the AP model in rats, without causing changes in spontaneous locomotion of the rats.


Asunto(s)
Dolor Abdominal/prevención & control , Analgésicos/farmacología , Antiinflamatorios/farmacología , Bloqueadores de los Canales de Calcio/farmacología , Canales de Calcio/efectos de los fármacos , Hiperalgesia/prevención & control , Umbral del Dolor/efectos de los fármacos , Pancreatitis/prevención & control , Dolor Abdominal/etiología , Dolor Abdominal/metabolismo , Dolor Abdominal/fisiopatología , Animales , Conducta Animal/efectos de los fármacos , Canales de Calcio/metabolismo , Señalización del Calcio/efectos de los fármacos , Ceruletida , Modelos Animales de Enfermedad , Conducta Exploratoria/efectos de los fármacos , Hiperalgesia/etiología , Hiperalgesia/metabolismo , Hiperalgesia/fisiopatología , Mediadores de Inflamación/metabolismo , Masculino , Neuropéptidos/farmacología , Páncreas/efectos de los fármacos , Páncreas/metabolismo , Pancreatitis/inducido químicamente , Pancreatitis/metabolismo , Pancreatitis/fisiopatología , Ratas Wistar , Venenos de Araña/farmacología , Médula Espinal/efectos de los fármacos , Médula Espinal/metabolismo , Médula Espinal/fisiopatología , omega-Conotoxinas/farmacología
10.
Toxicon ; 188: 80-88, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33038354

RESUMEN

Opioids are the "gold standard" treatment for postoperative pain, but these drugs also have limiting adverse effects. Thus, adjuvant drugs might be useful in opioid therapy for postoperative pain. The aim of the present study was to evaluate the effect of Phα1ß, a dual blocker of Cav2 and TRPA1 channels, on antinociceptive and adverse actions of morphine in a model of postoperative pain. Phα1ß (100-300 pmol/site) or morphine (3-10 mg/kg), alone, largely reduced postoperative nociception. However, Phα1ß (100 pmol/site) or morphine (10 mg/kg) also produced motor impairment. Lower doses of Phα1ß (30 pmol/site) or morphine (1 mg/kg), that did not have an effect alone, showed antinociceptive effect when concomitantly administrated. Moreover, co-administration of Phα1ß (30 pmol/site) with morphine (1 or 10 mg/kg) was unable to cause motor impairment. Preoperative repeated treatment with morphine increased the expression of Cav2 and TRPA1 channels in spinal cord, and caused tolerance and withdrawal syndrome, which were reversed with a single injection of Phα1ß (30 pmol/site). When injected postoperatively, escalating doses of morphine worsened postoperative hyperalgesia, induced tolerance, and withdrawal syndrome. Similarly, Phα1ß (30 pmol/site) reversed these adverse effects. Single or repeated morphine caused constipation, which was not altered by Phα1ß. Thus, a low dose of Phα1ß potentiated the analgesia, and reversed some adverse effects of morphine on operated mice, indicating the potential use of this agent as an adjuvant drug in opioid therapy for postoperative pain.


Asunto(s)
Analgésicos Opioides/uso terapéutico , Quimioterapia Adyuvante/métodos , Dolor Postoperatorio/tratamiento farmacológico , Venenos de Araña/uso terapéutico , Analgésicos , Animales , Canales de Calcio Tipo N/metabolismo , Hiperalgesia/inducido químicamente , Ratones , Morfina , Venenos de Araña/farmacología , Canal Catiónico TRPA1/metabolismo
11.
Toxins (Basel) ; 12(3)2020 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-32155765

RESUMEN

Spiders of the genus Loxosceles, popularly known as Brown spiders, are considered a serious public health issue, especially in regions of hot or temperate climates, such as parts of North and South America. Although the venoms of these arachnids are complex in molecular composition, often containing proteins with distinct biochemical characteristics, the literature has primarily described a family of toxins, the Phospholipases-D (PLDs), which are highly conserved in all Loxosceles species. PLDs trigger most of the major clinical symptoms of loxoscelism i.e., dermonecrosis, thrombocytopenia, hemolysis, and acute renal failure. The key role played by PLDs in the symptomatology of loxoscelism was first described 40 years ago, when researches purified a hemolytic toxin that cleaved sphingomyelin and generated choline, and was referred to as a Sphingomyelinase-D, which was subsequently changed to Phospholipase-D when it was demonstrated that the enzyme also cleaved other cellular phospholipids. In this review, we present the information gleaned over the last 40 years about PLDs from Loxosceles venoms especially with regard to the production and characterization of recombinant isoforms. The history of obtaining these toxins is discussed, as well as their molecular organization and mechanisms of interaction with their substrates. We will address cellular biology aspects of these toxins and how they can be used in the development of drugs to address inflammatory processes and loxoscelism. Present and future aspects of loxoscelism diagnosis will be discussed, as well as their biotechnological applications and actions expected for the future in this field.


Asunto(s)
Fosfolipasa D/historia , Hidrolasas Diéster Fosfóricas/historia , Venenos de Araña/historia , Animales , Catálisis , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Fosfolipasa D/química , Fosfolipasa D/farmacología , Hidrolasas Diéster Fosfóricas/química , Hidrolasas Diéster Fosfóricas/farmacología , Proteómica , Proteínas Recombinantes/farmacología , Picaduras de Arañas/diagnóstico , Picaduras de Arañas/tratamiento farmacológico , Picaduras de Arañas/enzimología , Venenos de Araña/química , Venenos de Araña/farmacología
12.
Pharmacol Rep ; 72(1): 47-54, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32016848

RESUMEN

BACKGROUND: Diabetic neuropathy is a common cause of painful diabetic neuropathy (PDN). C-X-C chemokine receptor type 4 (CXCR4) expression is increased in peripheral nerve samples from diabetes patients, suggesting a role for CXCR4 in PDN. Therefore, we evaluated the effects of Phα1ß, ω-conotoxin MVIIA, and AMD3100 in a model of streptozotocin (STZ)-induced PDN in rodents and naïve model of rats with the activation of the CXCR4/stromal cell-derived factor 1 (SDF-1) signal. METHODS: Diabetic neuropathy was induced by intraperitoneal (ip) injection of STZ in Wistar rats. Naïve rats were intrathecally injected with SDF-1 to test the CXCR4/SDF-1 signal. The effects of Phα1ß intrathecal (it), ω-conotoxin MVIIA intrathecal (it), and AMD3100 intraperitoneal (ip) on rat hypersensitivity, IL-6, and the intracellular calcium [Ca2+]i content of diabetic synaptosomes were studied. RESULTS: The drugs reduced the hypersensitivity in diabetic rats. SDF-1 (1.0 µg/it) administration in naïve rats induced hypersensitivity. Phα1ß (100 pmol/it) or AMD3100 (2.5 µg/ip) reduced this hypersensitivity after 2 h treatments, while ω-conotoxin MVIIA did not have an effect. IL-6 and [Ca2+]i content increased in the spinal cord synaptosomes in diabetic rats. The drug treatments reduced IL-6 and the calcium influx in diabetic synaptosomes. CONCLUSIONS: Phα1ß, ω-conotoxin MVIIA, and AMD3100, after 2 h of treatment of STZ-induced PDN, reduced hypersensitivity in diabetic rats. In naïve rats with CXCR4/SDF-1 activation, the induced hypersensitivity decreased after 2 h treatments with Phα1ß or AMD-3100, while ω-conotoxin MVIIA did not affect. The inhibitory effects of Phα1ß on PDN may involve voltage-dependent calcium channels.


Asunto(s)
Analgésicos/farmacología , Diabetes Mellitus Experimental/tratamiento farmacológico , Neuropatías Diabéticas/tratamiento farmacológico , Venenos de Araña/farmacología , Animales , Bencilaminas , Calcio/metabolismo , Canales de Calcio/metabolismo , Quimiocina CXCL12/metabolismo , Ciclamas , Diabetes Mellitus Experimental/complicaciones , Compuestos Heterocíclicos/farmacología , Ratas , Ratas Wistar , Receptores CXCR4/metabolismo , omega-Conotoxinas/farmacología
13.
J. venom. anim. toxins incl. trop. dis ; J. venom. anim. toxins incl. trop. dis;26: e20190104, 2020. graf, ilus
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1135148

RESUMEN

Spider venom is a potential source of pharmacologically important compounds. Previous studies on spider venoms reported the presence of bioactive molecules that possess cell-modulating activities. Despite these claims, sparse scientific evidence is available on the cytotoxic mechanisms in relation to the components of the spider venom. In this study, we aimed to determine the cytotoxic fractions of the spider venom extracted from Phlogiellus bundokalbo and to ascertain the possible mechanism of toxicity towards human lung adenocarcinoma (A549) cells. Methods: Spider venom was extracted by electrostimulation. Components of the extracted venom were separated by reversed-phase high performance liquid chromatography (RP-HPLC) using a linear gradient of 0.1% trifluoroacetic acid (TFA) in water and 0.1% TFA in 95% acetonitrile (ACN). Cytotoxic activity was evaluated by the MTT assay. Apoptotic or necrotic cell death was assessed by microscopic evaluation in the presence of Hoechst 33342 and Annexin V, Alexa FluorTM 488 conjugate fluorescent stains, and caspase activation assay. Phospholipase A2 (PLA2) activity of the cytotoxic fractions were also measured. Results: We observed and isolated six fractions from the venom of P. bundokalbo collected from Aurora, Zamboanga del Sur. Four of these fractions displayed cytotoxic activities. Fractions AT5-1, AT5-3, and AT5-4 were found to be apoptotic while AT5-6, the least polar among the cytotoxic components, was observed to induce necrosis. PLA2 activity also showed cytotoxicity in all fractions but presented no relationship between specific activity of PLA2 and cytotoxicity. Conclusion: The venom of P. bundokalbo spider, an endemic tarantula species in the Philippines, contains components that were able to induce either apoptosis or necrosis in A549 cells.(AU)


Asunto(s)
Animales , Venenos de Araña/farmacología , Apoptosis , Adenocarcinoma del Pulmón , Citotoxicidad Inmunológica
14.
Toxins (Basel) ; 11(6)2019 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-31248109

RESUMEN

Brown spider envenomation results in dermonecrosis with gravitational spreading characterized by a marked inflammatory reaction and with lower prevalence of systemic manifestations such as renal failure and hematological disturbances. Several toxins make up the venom of these species, and they are mainly peptides and proteins ranging from 5-40 kDa. The venoms have three major families of toxins: phospholipases-D, astacin-like metalloproteases, and the inhibitor cystine knot (ICK) peptides. Serine proteases, serpins, hyaluronidases, venom allergens, and a translationally controlled tumor protein (TCTP) are also present. Toxins hold essential biological properties that enable interactions with a range of distinct molecular targets. Therefore, the application of toxins as research tools and clinical products motivates repurposing their uses of interest. This review aims to discuss possibilities for brown spider venom toxins as putative models for designing molecules likely for therapeutics based on the status quo of brown spider venoms. Herein, we explore new possibilities for the venom components in the context of their biochemical and biological features, likewise their cellular targets, three-dimensional structures, and mechanisms of action.


Asunto(s)
Hidrolasas Diéster Fosfóricas , Venenos de Araña , Analgésicos/farmacología , Animales , Antiinflamatorios/farmacología , Antineoplásicos/farmacología , Humanos , Inmunoterapia , Insecticidas/farmacología , Fármacos Neuroprotectores/farmacología , Péptidos/farmacología , Hidrolasas Diéster Fosfóricas/química , Hidrolasas Diéster Fosfóricas/farmacología , Proteínas Recombinantes/farmacología , Inhibidores de Serina Proteinasa/farmacología , Venenos de Araña/química , Venenos de Araña/farmacología , Proteína Tumoral Controlada Traslacionalmente 1
15.
Toxicon ; 163: 12-18, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30880186

RESUMEN

Spider venoms are widely recognized as a new emerging source of potential research tools, pesticides, drug leads, and therapeutic agents. Some studies suggest that these venoms may contain interesting vasodilator compounds with potential therapeutic applications. In the present study, the vasodilator activity of the venom of Poecilotheria regalis was evaluated in isolated rat aortic rings. This venom induced an endothelium-dependent vasodilation [EC50 value was 5.52 (4.18-7.32) µg protein/ml with an Emax = 103.4 ±â€¯3.8%]. While the percentage of vasodilation induced by the venom was significantly diminished in the presence of a nitric oxide synthase inhibitor (L-NAME), it remained unaltered in the presence of suramin, a P2-purinergic receptor antagonist. Moreover, the vasodilator activity of the venom was not affected after boiling bath incubation, but was significantly decreased under reducing conditions. Additionally, venom composition was analyzed by reverse-phase chromatography and MALDI-TOF mass spectrometry, and two fractions were obtained, referred to as peptidic and non-peptidic fractions. Interestingly, both fractions induced vasodilation in isolated rat aortic rings. The results of this study showed that the venom of P. regalis induces a concentration-dependent vasodilation in rat aorta that was endothelium-dependent and involves the activation of NO/cGMP pathway. These results suggest that the venom contains a combination of both peptidic and non-peptidic vasodilator components. This study provides pharmacological data that suggest that P. regalis venom may be an important source of peptidic and non-peptidic vasodilator compounds.


Asunto(s)
Venenos de Araña/farmacología , Arañas , Vasodilatación/efectos de los fármacos , Animales , Aorta/efectos de los fármacos , GMP Cíclico/metabolismo , Endotelio Vascular/efectos de los fármacos , Femenino , Técnicas In Vitro , Masculino , Óxido Nítrico/metabolismo , Ratas , Ratas Wistar , Venenos de Araña/química , Vasodilatadores/farmacología
16.
J Sex Med ; 16(3): 365-374, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30773502

RESUMEN

INTRODUCTION: With the aim of overcoming the high toxicity of PnTx2-6 (or δ-CNTX-Pn2a), a toxin from the venom of the armed spider (Phoneutria nigriventer), the 19-aminoacid peptide, PnPP-19 (P nigriventer potentiator peptide), was synthesized based on molecular modeling studies of PnTx2-6. PnPP-19 improved the erectile function of normotensive rats and mice, without eliciting side effects, and no signs of toxicity were observed. In addition, PnPP-19 was able to potentiate the effect of sildenafil. AIM: To evaluate the efficacy of PnPP-19 in hypertensive and diabetic mouse/rat models in restoring erectile function, after topical administration; verify the biodistribution of PnPP-19 administration (topical and intravenous), permeation, and cyclic guanosine monophosphate (cGMP)/nitric oxide via implication. METHODS: Corpus cavernosum relaxation was evaluated using cavernous strips from male spontaneous hypertensive rats (SHR) and from streptozotocin (STZ)-diabetic mice contracted with phenylephrine and submitted to electrical field stimulation before and after incubation with PnPP-19 (10-8 mol/L, 10 minutes) or vehicle. This procedure was also used to determine cGMP/nitric oxide levels, at 8 Hz and to check the effect of PnPP-19 with sildenafil citrate. Biodistribution assays were performed using iodine 123-radiolabeled PnPP-19. In vivo erectile function was evaluated using intracavernosal pressure/main arterial pressure ratio in STZ-diabetic rats after PnPP-19 topical administration. MAIN OUTCOME MEASURES: PnPP-19 may become a new drug able to fill the gap in the pharmacologic treatment of erectile dysfunction, especially for hypertensive and diabetic individuals RESULTS: PnPP-19 potentiated corpus cavernosum relaxation, in both control and SHR rats. SHR-cavernosal tissue treated with PnPP-19 (1-32 Hz) reached the same relaxation levels as control Wistar rats (16 and 32 Hz). PnPP-19 treatment improved cavernosal tissue relaxation in STZ-diabetic mice and rats. PnPP-19 enhanced cGMP levels in STZ-diabetic mice corpus cavernosum strips. After topical or intravenous administration in rats, 123I-PnPP-19 was mainly recruited to the penis. When topically administered (400 µg/rat), PnPP-19 restores erectile function in STZ-diabetic rats, also improving it in healthy rats by increasing the intracavernosal pressure/main arterial pressure ratio. PnPP-19 exhibited an additive effect when co-administered with sildenafil, showing a novel mode of action regardless of phosphodiesterase type 5 inhibition. CLINICAL IMPLICATIONS: PnPP-19 seems to be an indicated drug to be tested to treat ED in diabetic and hypertensive patients. STRENGTH & LIMITATIONS: PnPP-19, although active by topical application and showing safety to human beings (not shown), has low permeability, about 10% of the applied dose. CONCLUSION: Our results showed that PnPP-19 may emerge as a potent new drug that can be topically administered, becoming a promising alternative for erectile dysfunction treatment. Nunes da Silva C, Pedrosa Nunes K, De Marco Almeida F, et al. PnPP-19 Peptide Restores Erectile Function In Hypertensive And Diabetic Animals Through Intravenous And Topical Administration. J Sex Med 2019;16:365-374.


Asunto(s)
Diabetes Mellitus Experimental/tratamiento farmacológico , Disfunción Eréctil/tratamiento farmacológico , Péptidos/farmacología , Venenos de Araña/farmacología , Administración Intravenosa , Administración Tópica , Animales , GMP Cíclico/metabolismo , Disfunción Eréctil/fisiopatología , Masculino , Ratones , Ratones Endogámicos C57BL , Óxido Nítrico/metabolismo , Erección Peniana/efectos de los fármacos , Inhibidores de Fosfodiesterasa 5/farmacología , Ratas , Ratas Endogámicas SHR , Ratas Sprague-Dawley , Ratas Wistar , Citrato de Sildenafil/farmacología , Estreptozocina , Distribución Tisular
17.
J Cell Physiol ; 234(2): 1398-1415, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30078202

RESUMEN

The mechanisms of cancer involve changes in multiple biological pathways. Multitarget molecules, which are components of animal venoms, are therefore a potential strategy for treating tumors. The objective of this study was to screen the effects of Phoneutria nigriventer spider venom (PnV) on tumor cell lines. Cultured human glioma (NG97), glioblastoma (U-251) and cervix adenocarcinoma (HeLa) cells, and nontumor mouse fibroblasts (L929) were treated with low (14 µg/ml) and high (280 µg/ml) concentrations of PnV, and analyzed through assays for cell viability (thiazolyl blue tetrazolium blue), proliferation (carboxyfluorescein succinimidyl ester), death (annexin V/propidium iodide [Pi]), the cell cycle (Pi), and migration (wound healing and transwell assay). The venom decreased the viability of U-251 cells, primarily by inducing cell death, and reduced the viability of NG97 cells, primarily by inhibiting the cell cycle. The migration of all the tumor cell lines was delayed when treated with venom. The venom significantly affected all the tumor cell lines studied, with no cytotoxic effect on normal cells (L929), although the nonglial tumor cell (HeLa) was less sensitive to PnV. The results of the current study suggest that PnV may be composed of peptides that are highly specific for the multiple targets involved in the hallmarks of cancer. Experiments are underway to identify these molecules.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Antineoplásicos/farmacología , Neoplasias Encefálicas/tratamiento farmacológico , Puntos de Control del Ciclo Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Glioma/tratamiento farmacológico , Venenos de Araña/farmacología , Neoplasias del Cuello Uterino/tratamiento farmacológico , Adenocarcinoma/patología , Animales , Apoptosis/efectos de los fármacos , Neoplasias Encefálicas/patología , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Femenino , Glioma/patología , Células HeLa , Humanos , Masculino , Ratones , Necrosis , Invasividad Neoplásica , Neoplasias del Cuello Uterino/patología
18.
Amino Acids ; 51(3): 433-449, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30449002

RESUMEN

Antimicrobial peptides present a broad spectrum of therapeutic applications, including their use as anticancer peptides. These peptides have as target microbial, normal, and cancerous cells. The oncological properties of these peptides may occur by membranolytic mechanisms or non-membranolytics. In this work, we demonstrate for the first time the cytotoxic effects of the cationic alpha-helical antimicrobial peptide LyeTx I-b on glioblastoma lineage U87-MG. The anticancer property of this peptide was associated with a membranolytic mechanism. Loss of membrane integrity occurred after incubation with the peptide for 15 min, as shown by trypan blue uptake, reduction of calcein-AM conversion, and LDH release. Morphological studies using scanning electron microscopy demonstrated disruption of the plasma membrane from cells treated with LyeTx I-b, including the formation of holes or pores. Transmission electron microscopy analyses showed swollen nuclei with mild DNA condensation, cell volume increase with an electron-lucent cytoplasm and organelle vacuolization, but without the rupture of nuclear or plasmatic membranes. Morphometric analyses revealed a high percentage of cells in necroptosis stages, followed by necrosis and apoptosis at lower levels. Necrostatin-1, a known inhibitor of necroptosis, partially protected the cells from the toxicity of the peptide in a concentration-dependent manner. Imaging flow cytometry confirmed that 59% of the cells underwent necroptosis after 3-h incubation with the peptide. It is noteworthy that LyeTx I-b showed only mild cytotoxicity against normal fibroblasts of human and monkey cell lines and low hemolytic activity in human erythrocytes. All data together point out the anticancer potential of this peptide.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/farmacología , Apoptosis/efectos de los fármacos , Fibroblastos/patología , Glioblastoma/patología , Neuroblastoma/patología , Venenos de Araña/farmacología , Arañas/química , Animales , Autofagia , Permeabilidad de la Membrana Celular , Células Cultivadas , Fibroblastos/efectos de los fármacos , Glioblastoma/tratamiento farmacológico , Hemólisis/efectos de los fármacos , Humanos , Necrosis , Neuroblastoma/tratamiento farmacológico
19.
Basic Clin Pharmacol Toxicol ; 124(5): 615-620, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30449066

RESUMEN

Phα1ß peptide isolated from the venom of the Phoneutria nigriventer spider has shown higher analgesic action in pre-clinical studies than ω-conotoxin MVIIA peptide used to treat severe chronic pain. In view of the great potential for the development of a new Phα1ß-based drug, a Phα1ß recombinant form (CTK 01512-2) has been studied for efficacy and safety. The aim of this study was to evaluate cytotoxic, genotoxic and mutagenic effects of a Phα1ß recombinant form and compare it with native Phα1ß and ω-conotoxin MVIIA. Cytotoxicity was evaluated using the MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) colourimetric assay in L929 mouse fibroblast cells (0.5-10.0 µmol/L). Genotoxic and mutagenic activities were analysed using the alkaline comet assay in peripheral blood and spinal cord, and the micronucleus test in bone marrow from Wistar rats treated by intrathecal injection of CTK 01512-2 (200, 500 and 1000 pmol/site), native Phα1ß (500 pmol/site) and ω-conotoxin MVIIA (200 pmol/site). CTK 01512-2 decreased the cell viability of the L929, showing IC50 of 3.3 ± 0.1 µmol/L, while the Phα1ß and ω-conotoxin MVIIA did not show cytotoxicity (IC50  > 5.0 µmol/L). Native and recombinant Phα1ß forms induced DNA damage in the spinal cord, but not in peripheral blood. CTK 01512-2 at 1000 pmol/site increased the micronucleus frequency suggesting mutagenic effects. In conclusion, the recombinant form has cytotoxic, genotoxic and mutagenic effects, evidenced in doses five times above the therapeutic dose.


Asunto(s)
Daño del ADN , Neurotoxinas/farmacología , Péptidos/farmacología , Venenos de Araña/farmacología , Médula Espinal/efectos de los fármacos , Analgésicos/farmacología , Analgésicos/toxicidad , Animales , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Fibroblastos/efectos de los fármacos , Concentración 50 Inhibidora , Masculino , Ratones , Pruebas de Mutagenicidad , Mutágenos , Neurotoxinas/toxicidad , Ratas , Ratas Wistar , Venenos de Araña/toxicidad , omega-Conotoxinas/farmacología
20.
Toxicol Lett ; 299: 67-75, 2018 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-30261224

RESUMEN

The present study was undertaken to characterize the behavioral manifestations of nociception and the local mechanisms involved with the nociceptive response elicited by Latrodectus curacaviensis venom (LCV) in mice. After the intraplantar LCV inoculation, spontaneous nociception, mechanical and thermal nociceptive thresholds, motor performance, edema and cytokine levels were evaluated using von Frey filaments, hot/cold plate, rota-rod, plethismometer and ELISA, respectively. Analysis of LCV was performed by SDS-PAGE and chromatography. Intraplantar injection of LCV (1-100 ng/paw) induced intense and heat-sensitive spontaneous nociception, mediated by serotonin and bradykinin receptors, TRPV1 channels, as well as by transient local inflammation. LCV (0.1-10 ng/paw) induced mechanical allodynia, which was reduced by the local pretreatment with H1 receptor or TRPV1 antagonists. Corroborating the TRPV1 involvement, in thermal nociception assays, LCV induced a similar response to that of capsaicin, a TRPV1 agonist, facilitating the response to noxious hot stimuli and inhibiting the response to cold noxious stimulation. LCV promoted mast cell degranulation, increased IL-1ß paw levels, but did not produce a relevant edematogenic effect. Analysis of LCV components showed a predominance of high molecular weight proteins. This work provides the first mechanistic hypothesis to explain the local pain induced by LCV, the most frequent clinical symptom of human envenomation.


Asunto(s)
Conducta Animal/efectos de los fármacos , Fasciculación/inducido químicamente , Dolor Nociceptivo/inducido químicamente , Venenos de Araña/farmacología , Animales , Degranulación de la Célula/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Masculino , Mastocitos/efectos de los fármacos , Ratones , Actividad Motora/efectos de los fármacos , Dimensión del Dolor , Umbral del Dolor , Arañas
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